Source Code does what a good Sci-Fi film (and story) should do: use a science-based fantasy to tell a humanistic story. It is an engaging film, enjoying a well-matched cast led by Jake Gyllenhaal who reminds us how good he can be, and directed confidently by Duncan Jones.
When Source Code starts, it feels like a mixture of Groundhog Day with the Matrix, combined with Murder on the Orient Express as well as the more recent Unstoppable, but it quickly comes to a form of its own, comparable to none. In terms of pacing, the film loses steam and focus mid-way but it picks it up again, coming up to a mind-boggling crescendo, making up for the lost time.
The way the film handles a multitude of subject matters in the subtlest manner is admirable. These include the ancient question of fate versus destiny, the topic of human rights (both in terms of the right of a person for life termination and in terms of being a ‘military property’), military obedience (personal morals vs answering to a chain of command,) etc. Quite a lot is compacted into this story and credits go to Ben Ripley, the writer. I also favored that, ultimately, the writer does take a stand in the famous Sci-Fi paradox of multiple realities, rather than leave it vague. It is done in a smart and satisfying manner which I will not disclose here as it will be a plot spoiler. Source Code comes close to greatness but I am keeping it at 4 stars as it takes a little too much time to find the right tracks.